Toyota Aims to Eliminate CO2 Emissions of Building

Toyota Motor has introduced a solar power generation system, storage battery and pure hydrogen-type fuel cell co-generation system at its main factory in Toyota City, Aichi Prefecture, Japan, and started test operation.

They were installed in the “Energy Management Building,” which Toyota built on the premises of the factory in August 2016.

The output of solar panels is 40kW while the capacity of the storage battery is 10kWh. The rated output of the fuel cell system is 3.5kW. Electricity generated by the solar power generation system is not sold by using the feed-in tariff (FIT) scheme. Instead, all the electricity is consumed in house, and surplus electricity is stored in the battery. Those operations are optimally controlled by an energy management system (EMS).

While the energy demand of the Energy Management Building is estimated by using the EMS, demand control is carried out. Toyota tests operation aimed at minimizing CO2 emissions by combining solar power generation, whose output fluctuates, and the storage battery, using the power supply from the fuel cell system as a base.

For the storage battery, the nickel-metal-hydride (NiMH) batteries of the Prius were reused. The fuel cell system was developed by Toshiba Corp for small-scale offices. And this is the first time that it has been operated for commercial use.

The fuel cell system uses hydrogen as fuel without making any changes to it. Therefore, the system can generate electricity without generating CO2 and can be started up in a short period of time. The electricity generated and warm water produced in the power generation process are supplied to the Energy Management Building and used for air conditioning, etc.

Hydrogen is purchased from outside.

“Whether CO2 is emitted at the time of producing hydrogen depends on the vendor,” Toyota said. “We will also consider producing hydrogen by using renewable energy such as solar power to electrolyze water in the future.”

Toyota announced “Factory CO2 Zero Challenge” in 2015, and, since then, has been making efforts to eliminate CO2 emitted from its manufacturing plants. This time, in the newly-built Energy Management Building, the company aims to realize zero CO2 emissions by using energy-saving measures, renewable energy and hydrogen system.

Toshiba not only supplied the fuel cell system but also participates in the operation of the facilities. In the test, the company is responsible for the prediction of energy (electricity and heat) demand based on the actual operation and the development of technologies to optimally operate the facilities.